Fluted slag pot



July 14, 1936. I c w HOWAT 2,047,473

. FLUTED SLAG POT Filed Nov. 5, 1932 6 SheetsSheet 1 w/r/vssszss g INVENTOK.

A TTORNEYJ July 14, 1936. c w HOWAT 2,047,473

FLUTED SLAG POT Filed Nov. 5 1932 6 Sheets-Sheet 2 IN VE N TOR.

M A TTORNE Y3 July 14, 1936. c, w, HOWAT 2,047,473

FLUTED SLAG POT V Filed Nov. 3, 1952 6 Sheets-Sheet 3 6%- W M W $5 M A TTORNE Y8 C. W. HOWAT FLUTED SLAG POT July 14, 1936.

Filed Nov. 5, 1932 6 Sheets-Sheet 4 mzmd fl la ATTORNEYj WITNESSES July 14, 1936. c w, H w 2,047,473

FLUTED SLAG POT Filed Nov. 5, 1932 6 Sheets-Sheet 5 Mrwzasts v INVENTOR.

ATTORNEYS Patented Jully 14, 1936 STATES FLUTED SLAG POT Application November s, 1932, Serial No. $40,925

Claims.

This invention relates to cinder pots, or slag pots, such as are generally employed in the operation of metallurgical plants for handling hot slags resulting from the smelting or refining of 5 metals such, for example, as iron, steel or copper. Such slag or cinder pots have usually been in the form of an inverted thimble or cone having a. rounded or spherically curved bottom portion. Since these pots receive the slag when it is fluid and at the melting temperature of the metal they are usually a unitary casting of iron or steel. This method of fabrication has substantially replaced the construction of such pots in sections which has been employed to a limited extent in the past in order to provide for re placement of portions of the pots and thereby avoid discarding them entirely.

Slag pots or cinder pots are generally supported on trunnion rings resting on cradles or mounted on cars for transportation from the point of receiving the slag to the point at which the slag is to be delivered or discharged. Also these pots are often handled by cranes or similar lifting devices to and from the cars while the pots are loaded with the molten slag which is, of course, relatively heavy. In such handling of the pots they are usually suspended by means of stools or chairs attached to the upper portions of the shells and supported by the trunnion rings.

It will be readily appreciated that pots for handling molten material at highly elevated temperatures and of relatively great weight are subjected not only to severe and rapid temperature changes which tend to create internal stresses in the metal structure of the walls of the pots, but the latter are also subjected to severe strains as a result of their handling either by cranes or by cars, in either case the weight of the pot and its contents being supported by the upper portion of the pots.

It is necessary therefore in order to prevent deformation and rapid deterioration of the walls of the pots to provide special means for rein forcing the portions of the walls that are subjected to-considerable stress in order that the life of the'pot may be prolonged. Such reinforcing means are necessary by reason of the fact that the normal strength of the materials of which the pots are constructed is materially reduced at the high temperatures which their shells. assume when filled with molten slag or similar charges.

In the provision of suitable reinforcing means care must be taken that the stresses to which the walls are subjected are not increased thereby as such arrangement while strengthening portions of the walls would only hasten the deterioration of the pot as a whole by reason of the localized 5 stresses set up by some forms of reinforcements. For example, some of the reinforcing means employed in prior art structures have taken the form of increased metal thickness at desired portions of the pots and such reinforcements have been in the nature of bands, ribs or pads attached to the outer surface of the shell of the pot.

While such reinforcing devices have to a certain degree relieved the stress on the metal that 5 has arisen during the handling of the pots, they have also increased the stress in these portions of the wall structures originating from rapid temperature changes and the resulting temperature differential between various portions of the shell and accordingly such means have frequently contributed to the premature discarding of the pot. It has been proposed heretofore also to provide corrugations in the walls of the shell for the purpose of relieving stresses due to temperature variations by providing a certain degree of mechanical flexibility. Such construction while diminishing the breakage or cracking of the shell walls to a degree has not overcome the deformation of the shell with its resulting difiiculty in discharging the contents of the pot. Such difficulty may be serious after the slag has frozen or solidified into a single mass upon cooling, whereupon any deformation of the pot may render its removal an extremely diflicult matter.

In accordance with the present invention I provide slag pots or cinder pots having side walls that are reinforced both vertically and horizontally for the purpose of resisting stresses to which the side walls are subjected during the operation of loading and transporting the relatively heavy material at high temperature for which they are employed.

The walls are reinforced both horizontally and vertically without the employment of localized built-up sections.

For vertical stiffening purposes, the side walls are provided with flutes or indentations constituting hollow ribs which vary in depth or departure from the general outline of the pot as they progress from the top toward the bottom of the pot. In one form of my invention the depth of the flutes is greater at the top of the pot than at the bottom in order that the inner surfaces of such flutes may operate as skids or inclines upon which the solidified contents of the pot may slide when the pot is tilted for discharge of its contents.

It has been found that the magnitude of the forces to which the walls of the pots are subjected during the operation of the latter may exceed the elastic limit of the metal of the shells and particularly after repeated filling of the pots with the hot slag. Fatigue of the metal resulting from such frequent bending of the walls at this stage in the life of the pot is characterized by incipient deformation of the pot which must be prevented or its discard will follow at a comparatively early date.

For the purpose of preventing such incipient deformation I have provided the edges of the indentations or flutes with bands extending thereacross and bridging the depth of the indentations. If such bands are curved outwardly they form with the initially curved indentation a section which may be termed a hollow oval or a hollow rib.

Such bands, by reason of the relatively small portion connected to the metal of the shell, are subject only to relatively small temperature variations, and such heat as may be transmitted thereto is readily dissipated from their comparatively large surface area that is entirely exposed to the surrounding atmosphere. The bands remain at a substantially constant temperature approximately that of the atmosphere, and also at substantially constant length thereby preventing the edges of the indentations or flutes from spreading and thus preserving the normal shape of the pot.

The horizontal reinforcing means is preferably provided in the form of a ring portion which extends substantially horizontally and is continuous with the walls of the pot. When this form of construction is employed the cross-sectional areas of the pots vary in steps at such horizontal rings. It will be appreciated that the strength of such horizontal rings varies in accordance with the width of the annular band or ring, acting as a circular girder.

The provision of such horizontal rings or steps in the side walls of pots, and particularly above the supporting means therefor, such, for example, as trunnion rings, not only provides reinforcing means for maintaining the shape or form of the pot but also provides increased capacity of the pots because of the enlarged diameters above the steps or horizontal rings.

Reinforcements constructed in the manner described above very materially increase the strength of the side walls of the pots without adding a proportionate amount of material thereto. They serve to maintain the normal shape of the pots substantially irrespective of temperature variations, and such reinforcement is effective in both horizontal and vertical directions.

The details of my invention will be described in connection with the accompanying drawings, in which Fig. 1 is a view in side elevation of a car for supporting a cinder pot or slag pot constructed in accordance with my invention;

Fig. 2 is a view in end elevation of a car and a slag pot of modified design supported thereby;

Fig. 3 is a plan view of a slag pot substantially similar to that of the slag pot of Fig. 2;

Fig. 4 is a vertical sectional view taken on line IV-IV of Fig. 3;

Fig. 5 is a plan view of a modification;

Fig. 6 is a view partially in vertical section and partially in elevation of the slag pot of Fig. 5;

Fig. 7 is a plan view of a pot of oblong shape;

Fig. 8 is a vertical sectional view taken on line VIII-VIII of Fig. '7; I

Fig. 9 is a vertical sectional view of a portion of the slag pot of Fig. 7 taken on line IX-IX thereof; and

Figs. 10, 11 and 12 are enlarged sectional views .of portions of the side walls of the slag pot of Fig. 9 and taken on lines X--X, Xi-XI and XII-JG]: of Fig. 9, illustrating the shapes of hollow ribs at progressively lower elevations in the side walls.

In the various views of the drawings, similar numerals designate like parts.

Referring to Fig. 1, a car I of the type generally known as a cinder car, and commonly employed in plants for the manufacture of iron and steel, is provided with suitable means for supporting a cinder pot orslag pot 2. Above each of the trucks 3 of the car are standards 6 each having two suitably spaced bearings therein for supporting a trunnion ring 5 having two trunnions 6 at each end thereof as shown in Fig. 2. The standards 4 and the trunnion ring 5, together with its supporting means, constitutes in effect a cradle for supporting the slag pot 2.

The trunnion ring 5 is provided at its opposite ends with spool-like trunnions l by means of which the trunnion ring 5, with the slag pot 2 supported thereon, may be engaged by a crane.

The pot 2 is provided on its outer surface with lugs 8 or brackets which may be termed stools or chairs for the purpose of resting the weight of the pot upon the trunnion ring 5. These stools 8 are rigidly secured to the outer surface of the walls of the pot.

The pot 2 is of the inverted thimble type and is provided at its upper portion with flutes or indentations 9 that extend from the top of the pot toward the bottom thereof gradually increasing in width but decreasing in depth. These details, however, will be later described. The bottom portion ll] of the pot 2 is curved or rounded, and of such shape as to be continuous with the portion that is indented or fluted.

It will be noted that the pot 2 is provided with a step or horizontal ring I I immediately above the trunnion ring 5 which serves the purpose not only ofreinforcing the pot but of providing additional capacity by reason of the greater cross-sectional area provided thereby.

In the arrangement shown in Fig. 2 the car I3 is provided with relatively short standards I 4 for supporting the trunnions 6 of a trunnion ring 5. A car of this construction provides that a slag pot of relatively greater diameter may be employed than would be the case if the standards I4 were relatively high as in the construction of Fig. 1. The details of the slag pot I'l other than the general shape thereof do not differ material- 1y from those of the pot 2 of Fig. 1.

Reference may now be had .0 the slag pot shown in Figs. 3 and 4. The details of construction of this form of my invention are in general similar to those of the pots 2 and ll of Figs. 1 and 2, respectively. The pot 20 is provided with inwardly extending flutes of indentations 2| having convex inner surfaces that widen gradually and diminish in depth as they extend from the top toward the bottom of the pot. This arrangement insures that when the pot is tilted to provide for the discharge of slag that has solidifiedor frozen therein the body of the slag will be lifted from its contact with the side walls of the pot as it slides outwardly, and the flutes will faces uponwhich the slag rests after its initial I substantially contents of the slag pot.

movement.

At an intermediate portion of the pot there is provided a horizontal band or shelf 22 in the side walls thereof and integral with the latter and which serves as a reinforcing ring for preventing horizontal deformation of the pot. This ring 22 forms a step in the contour of the side walls of the pot. The relative position of a trunnion ring 5 with respect to the step 22 in the side Wall of the pot is shown in Fig. 4. The weight of the potis supported on stools 8, only one of which is shown, and the bottom portion of which engages the trunnion ring.

In order to prevent the slag pot 26 from falling out of the trunnion ring 5 when these parts are tilted for discharge of the contents, a latch 25 is provided below the trunnion ring 5 and is secured to a rib 26 by means of a pin 21. The lath 25 is placed in position after the pot 20 is placed on the ring 5 and when the pin 21 is inserted the latch 25 is prevented from rotating on the pin 21 by reason of its extending beyond the pin into locking position with the shell;

The lower end of the stools 8 and the upper end of the latches 25, a plurality of which may be provided, are spaced apart in order to provide for variations in length by reason of expansion due to the high temperature of the liquid Eye-bolts 28 may be cast directly within the side walls of the pot 20 on the top rim thereof for the purpose of handling the slag pot by means of cranes or suitable lifting devices.

The upper edge of the slag pot 20 is provided with a relatively thick portion or bead 29, to reinforce the upper edge of the pot. Such construction it desirable, not only for enabling the pot to resist strains caused by the weight of its contents, but also in order that it may provide sufiicient strength whereby the weight of the pot may be handled safely by means of the eye-bolts 28.

The indentations 2! and the step 22 respectively provide means for reinforcing the pct 20 against vertical and horizontal deformation. The arrangement also provides mechanical flexibility since changes in temperature and the resultant expansion of the walls may be compensated for by changes in the shapes of the flutes by reason of the elasticity or flexibility of the metal of which the pots are formed.

Referring to the form of invention illustrated in Figs. 5 and 6, the slag pot 30 is provided with indentations or flutes 3! which taper both in width and in depth from the top to the bottom of the pot. The outer edges of the indentations or flutes 3i are connected by means of curved tie bands 32 that are similar in construction to the tie bands 38 shown in Figs. 10, 11 and 12 in connection with the slag pot of Figs. 7, 8 and 9.

As stated above, these bands will remain at atmospheric temperature. The bands limit temporary bending of the flutes and thus prevent permanent deformation of the Walls at the flutes by reason of excessive expansion between the edges of the indentations. At the same time, the bands are sufliciently elastic to permit sufficient flexing of the side walls to avoid undue stresses therein.

These bands may be arranged in rings extending around the periphery of the pot 30 or they may be staggered with respect to adjacent flutes, or they may be arranged in any other suitable or desired manner. The pot 30 is provided with suitable lugs or ears 33 by means of which it may be handled by cranes having a suitable bail or by other means, and it is also provided with stools 34 by means of which the pot may be supported upon the usual trunnion ring when the pot is to be transported by a car. Suitable wear plates 35 are provided at spaced intervals around the pot 30. This form of slag pot is suitable for use in handling slags that are discharged while in a fluid state.

Reference may now be had to Figs. 7, 8 and 9 in which is illustrated a slag pot 36 of oblong form having a vertical section which is similar to that described in connection with the slag pot of Figs. 3 and 4. The slag pot 36 is provided with indentations 37 of the type that are deeper at the top of the pet than at the bottom thereof, and. which are gradually wider as they progress toward the bottom.

These indentations which taper both in depth and in width are provided on the exterior of the pot with tie bands 38 which bridge the outer edges for the purpose of preventing the permanent deformation of the flutes by reason of temperature variations. The bands 38 and the curved grooves 31 are shown in enlarged detail in Figs. 10, 11 and 12. This construction constitutes hollow ribs such as that described above in connection with the pot of Figs. 5 and 6.

In addition to the hollow ribs the slag pct 36 is provided with two steps 39 and 40 that are constituted by horizontal rings of material that are integral and continuous with the remainder of the walls and extend at angles thereto. These steps afford reinforcing means horizontally while the grooves 31 afiord reinforcing means against vertical deformation; In view of the extent of the relatively flat side walls of the slag pot 36 it is essential that ample means for preventing horizontal deformation of the pot be provided. While I have shown and described two steps or reinforcing rings the number may vary in accordance with the depth of the slag pot, the length of its flat surface or the force towhich it is to be subjected.

As best shown in Fig. 8, theslag pot 36 is provided with lugs or hooks 42 by means of which it may be handled and which may be provided in suitable number for this purpose. As in the case of. the slag pots described hereinabove, stools 43 are provided along the side walls for the purpose of supporting the weight of the slag pot upon a suitably shaped trunnion ring 34. Latches 35 in any suitable number may be provided along the side walls of the slag pot, and for purposes similar to those previously described.

The slag pot 36 which is oblong and is of a single integral piece of metal may be of a capacity at least three times that of the usual pot of circular cross section. For example, the usual pot may have a capacity of about 400 to 450 cu. ft. A larger pot of this shape would probably be of prohibitive width because of the relatively small clearances in plants where such pots are used. The oblong pot may have a capacity of 1200 cu. ft. or more.

Pots of this capacity have not been possible heretofore because it has been impossible to use a pot having straight sides for the service for which they are intended. It is necessary that strains incident to having the lower portion filled for several hours with molten slag while the upper portion is at substantially atmospheric temperature. No construction prior to that provided by the applicant has been able to remain in serviceable condition after being subjected to such operating conditions.

Applicant's construction wherein the sides are provided with flutes or corrugations together with the tie bands is sufliciently elastic that the side walls can adjust themselves to the widely different temperatures prevailing at difierent levels without rupture of the walls or without permanent distortion thereof.

The shape of the various pots having tapered fluted sides with smooth curved bottoms provides minimum contact between the slag and the bottom portion and provides strength and flexibility where it is needed. Greater flexibility is required at the top of the pots because the hot slag expands the bottoms first as the pots are filled and such flexibility is provided by the greater depth of the grooves at the tops of the pots.

The shelves or steps provided by the horizontal rings increase the capacity of the pots because the diameters of certain portions of the pots are usually limited by those of trunnion rings of existing equipment for handling pots.

Since the reinforcing means are integral and continuous with the shell structure and the latter is of uniform thickness substantially throughout and all parts of the shell are in contact with the contents thereof, expansion is very nearly uniform throughout the entire pot and stresses due to temperature are accordingly reduced to a min imum. There is no warping such as is caused by the presence of outside reinforcing ribs.

The bands for bridging the flutes permit sufficient flexibility to relieve stresses in the side walls of the pots but limit the extent of the separation of the edges of the grooves and thus prevent permanent deformation in a horizontal plane.

While the preferred manner of forming the slag pots of my invention is by casting in a single piece, it will be understood that they may, if desired, be formed in sections and assembled in any suitable manner.

From the foregoing it will be noted that I have provided slag pots of greatly improved construction, and of such arrangement that they will successfully resist the tendency. of temperature variations and the strains of loading and handling to cause deformation of the side walls of the slag pots. The reinforcing means for preventing both horizontal and vertical deformation have greatly strengthened the side walls of the slag pots without any material increase in weight. The improved reinforcing means has thus materially reduced deformation of the slag pots and correspondingly increased the length of their periods of service.

I claim:

1. A receptacle for molten slag or the like comprising a shell having sides tapering inwardly from top to bottom thereof and having a curved bottom portion in continuation of the sides, the sides comprising an upper portion and a lower portion that are horizontally offset with respect to each other, and said portions being connected by an integral reinforcing ring continuous therewith.

2. A receptacle for molten slag or the like comprising a shell having sides tapering inwardly from top to bottom thereof and having a curved bottom portion in continuation of the sides, the

sides comprising a lower portion and an upper portion that is offset outwardly horizontally from the lower portion and said portions being connected by a horizontal step portion continuous therewith and constituting a reinforcing ring for 5 said receptacle.

3. A receptacle for molten slag or the like comprising a shell tapering inwardly from top to bottom thereof and having a curved bottom portion in continuation of the sides, the sides being reinforced at a plurality of zones therein, each of said zones extending around said shell and the reinforced section for each zone comprising two portions of the inclined sides that are offset horizontally from each other and are joined by a ring extending at an angle to each of the two inclined side portions.

4. A receptacle for molten slag or the like comprising a unitary shell having sides tapeLlng inwardly toward the bottom thereof and a curved 20 bottom portion, said shell having flutes in its sides that extend downwardly from the top thereof at progressively diminishing depth therein, and bands for connecting opposite sides of said flutes at their outer edges to limit the separation of 25 said sides to prevent deformation of said shell.

5. A receptacle for molten slag or the like comprising a unitary shell having sides tapering inwardly toward the bottom thereof and a curved bottom portion, said shell having flutes in its sides that extend downwardly from the top thereof at progressively increasing width to constitute reinforcing channels for said shell, and means for connecting the outer open sides of said channels to limit the separation thereof when the v shell is subjected to stresses whereby deformation of the shell is prevented.

6. A receptacle for molten slagor the like comprising a unitary shell having sides tapering inwardly toward the bottom thereof and a curved bottom portion, said shell having flutes in its sides that extend downwardly from the top thereof at progressively diminishing depth and increasing width in said shell to constitute reinforcing channels therefor, and curved bands in approximate continuation of the contour of said shell for connecting opposite edges of said channels for limiting the separation thereof.

'7. A receptacle for molten slag or the like comprising a shell the side portions of which have the form of an inverted frustum of a cone and having a curved bottom portion in continuation of its sides, the side portions of said shell being provided with a series of flutes extending downwardly from the top of said shell to form reinforcing channels having open sides on the outside of said shell, and bands for connecting the shell across the open sides of said channels for preventing deformation of said shell.

8. A receptacle for molten slag or the like comprising a shell having sides inclined inwardly toward the bottom thereof and having also a curved bottom portion continuous with said sides, said sides being provided with a series of indentations extending from the top toward the bottom thereof to form vertical reinforcing channels and said sides being provided also with horizontally extending reinforcing means comprising a ring extending at an angle to the inclined sides and continuous therewith at an intermediate portion 70 thereof.

9. A receptacle for molten slag or the like comprising a shell having sides inclined inwardly toward the bottom thereof and having also a curved bottom portion continuous with said sides, 76

aoamre said sides being provided with a series of indentations extending from the top toward the bottom thereof to form vertical reinforcing channels and said sides being provided also with a plurality of horizontally ofiset portions or steps each comprising a ring portion extending around said shell and the plane of which is at an angle to the inclined sides of said shell.

10. The combination with a car having a supporting frame, a receptacle for molten material, and a trunnion ring surrounding said receptacle and supported upon said car by said frame, said receptacle having a portion above said trunnion ring that is oiTset outwardly horizontally with respect to the portion'within said trunnion ring and said portions being connected by a reinforcing ring continuous therewith, whereby the capacity of the receptacle is increased by the enlargement thereof above said trunnion ring.

11. The combination with a car having a supporting frame, a receptacle of circular crosssection for molten material, and a trunnion ring surrounding said receptacle and supported upon said car by said frame, said trunnion ring limiting the diameter of said receptacle below the top of said ring, said receptacle having an outwardly extending horizontal offset or integral step above said trunnion ring whereby the capacity of the receptacle is increased by the enlargement of the diameter thereof resulting from the oii'set and whereby the horizontal or step portion of the receptacle serves as an annular reinforcing ring.

12. A receptacle for molten slag or the likecomprising a member of oblong cross section having substantially straight sides provided with a ring extending horizontally therearound and integrally connecting offset portions of the side walls to reinforce the latter against horizontal deformation.

13. A receptacle for ,molten slag or the like comprising a member of oblong cross section having substantially straight sides provided with a series of flutes extending between upper and lower portions of the side walls to reinforce the latter against vertical deformation thereof and provided also with a horizontally extending ring along the sides thereof and continuous with ofl-= set portions of the walls to prevent horizontal deformation of said walls.

14. The combination with a car having a supporting frame, a trunnion ring of oblong shape supported on. said frame, and a receptacle of oblong cross section within and supported by said trunnion ring, said receptacle having substantially straight sides provided with a series of flutes extending between upper and lower poriions of the side walls to reinforce the latter against vertical deformation thereof, said flutes extending inwardly from the plane of the side walls and out of engagement with said trunnion ring.

15. A receptacle for molten slag or the like comprising a shell having sides tapering inwardly from top to bottom thereof and having a curved bottom portion in continuation of the sides, the sides comprising an upper and a lower portion that are horizontally ofiset with respect to each other and connected to each other by a continuous reinforcing ring integral with said portions, and said upper portion being provided with flutes extending downwardly from the top of the receptacle to said reinforcing ring.

CLARENCE W. HOWAT. 

